I don't understand how complicated software like this gets widely deployed and accepted when documentation on it is so limited and unclear... It is quite difficult to get ldap to function properly and am left with the question of how the hell anyone can figure out how to get this piece of software to do anything! If there was some form of acceptable documentation....
Do you understand the basics of LDAP (schema, partitioning, binding. naming conventions, etc....) - if not then you skipped a step and will possibly never get it working. My suggestion [not that anyone ever listens] is to first skip all the OpenLDAP documentation and read LDAP documentation; then come back to this specific implementation after you've got your head around the concepts of LDAP. LDAP is complicated, diving right into implementation is wrong approach.
I recommend - Understanding and Deploying LDAP Directory Services, ISBN-13: 978-0672323164 - to explain the LDAP part, it doesn't get hung up on any specific DSA (implementation of an LDAP server). Many newer texts see "LDAP" and "Active Directory" as interchangeable and thus don't teach you much of anything about LDAP. Most OpenLDAP related texts are obsolete before they hit the shelves.
HOWTOs, while useful, are not documentation. They only get you deeper into the hole of not-knowing-what-you-are-doing.
You will also need a side understanding of SASL and possibly NSS (depending on what you are doing). These are related technologies but not 'part of' LDAP or OpenLDAP thus documentation assumes you know what they are from other sources.
And OpenLDAP works very well, is fast and stable.